Black Mount

Lying 650m W of the summit of Black Mount and near the eastern extremity of a ridge which slopes gently down from Borland Hill, there is a ring enclosure within which there is a cairn. The site lies at 380m OD.

The 19m diameter enclosure is composed of an earth bank measuring 3m broad by 0.5m high. The grassy bank has no visible stone and it has a flattish top about 1m wide. There is an apparent depression around the summit of the bank, this may be attributable to animals walking around the top of it or may represent an aspect of the monument construction.

The cairn is 5m diameter by 0.3m high and is offset within the west side of the enclosure having a gap of 1m between it and the internal edge of the surrounding bank. The stony cairn has a flattish top but there is a 1m diameter depression in the centre, this is about 0.1m below the top of the cairn.

There is no apparent gap in the circuit of the bank and judging from the uniformity of the enclosure as it survives, it is unlikely that there was an entrance gap in the bank. There is no evidence of turf stripping around the enclosure as is sometimes seen at ring enclosures and which indicates the area where the construction materials were taken from. Similarly the interior appears to have the same angle (almost level) of sloping surface as the exterior ground surrounding the site. Therefore it appears that the bank material, whether originally soil or turf, has been brought to the site. A circa 0.75m irregular stone is showing above the ground level outside and on the immediate western side of the enclosure, it may be outcropping rock, it has no obvious significance.

There is some rush infestation, mostly in the form of a patch on the east side and on the bank at that side, there is also some patchy heather around the bank, otherwise the vegetation on and surrounding the site is short cropped grass.

On the 20th December 1998, and as viewed from the centre of this site, the sun was observed to set within 1deg to the left of the summit of Tinto Hill (231deg magnetic at that time) and the prominent cairn which lies there. The last glimpse of the sun disappeared before reaching the summit cairn at approximately 15.30 GMT. Tinto hill is 16.5km to the SW and the cairn is at 707m OD.

The event makes a convincing mid winter solstice sunset alignment, and implies that the enclosure may have been deliberately sited to facilitate observation of this event.

Furthermore, if a line between Tinto Hill and the enclosure is extended to the NE, the prominent summit of Mendick Hill (510 magnetic in 1998), 6.8km distant and 451m OD, can be seen centrally within the cross over of the NW flank of Black Mount and a subsidiary summit.

It is conjectured that this alignment will be a close indicator of mid summer sunrise. Should this prove to be so, it will be possible to observe and record the longest and shortest days of each year from the ring enclosure.

Tam Ward, Biggar Archaeology Group, 1999